Configuration

Complete reference for all Armchain node (armnode) command-line flags. You can also export a config file and customize it. See Configuration File (TOML) at the bottom.

General

Flag	Default	Description
--datadir	~/.armnode	Data directory for databases and keystore
--genesis	-	Path to genesis file (required for joining a network)
--config	-	Path to TOML configuration file
--fakenet	-	Run as fakenet validator (n/N format)
--cache	3600	Megabytes of memory allocated for internal caching (minimum 3600)
--syncmode	full	Blockchain sync mode (full, snap)
--gcmode	archive	Garbage collection mode (archive, full, light). Note: Unlike Geth, Armchain defaults to archive. See Node Types.
--db.preset	ldb-1	Database layout preset (ldb-1, pbl-1, legacy-ldb, legacy-pbl). See Node Types - Database Configuration.
--nousb	false	Disable USB hardware wallet monitoring. Note: Hardware wallets (USB/Ledger/Trezor) have not been upgraded to support ML-DSA44 PQC keys. This flag is retained for compatibility but HW wallet signing is not currently functional.
--verbosity	3	Log verbosity (0=silent, 1=error, 2=warn, 3=info, 4=debug, 5=detail)

Network (P2P)

Flag	Default	Description
--port	5050	P2P listening port
--maxpeers	50	Maximum number of network peers
--bootnodes	-	Comma-separated enode URLs for bootstrapping
--nat	any	NAT port mapping (any, none, upnp, extip:IP)
--nodiscover	false	Disable peer discovery
--netrestrict	-	Restrict network to CIDR ranges

HTTP JSON-RPC

Flag	Default	Description
--http	false	Enable HTTP RPC server
--http.addr	localhost	HTTP RPC listening address
--http.port	18545	HTTP RPC port
--http.api	eth,net,web3	Comma-separated API namespaces to expose
--http.corsdomain	""	Comma-separated list of allowed CORS domains
--http.vhosts	localhost	Comma-separated list of allowed virtual hosts

WebSocket

Flag	Default	Description
--ws	false	Enable WebSocket RPC server
--ws.addr	localhost	WebSocket listening address
--ws.port	18546	WebSocket port
--ws.api	eth,net,web3	Comma-separated API namespaces to expose
--ws.origins	-	Allowed WebSocket origins

Validator

Flag	Default	Description
--validator.id	-	Validator ID (required for validators)
--validator.pubkey	-	Validator public key (ML-DSA44 hex)
--validator.password	-	Path to file containing validator key password

RPC Limits

Flag	Default	Description
--rpc.gascap	50000000	Gas cap for eth_call and eth_estimateGas
--rpc.txfeecap	1	Transaction fee cap in ARM
--rpc.timeout	5s	HTTP RPC timeout
--rpc.allow-unprotected-txs	false	Allow non-EIP-155 transactions

Account Management

Flag	Default	Description
--allow-insecure-unlock	false	Allow account unlock over HTTP (dangerous!)
--unlock	-	Comma-separated account addresses to unlock
--password	-	Password file for account unlock

Performance Tuning

Flag	Default	Description
--cache	3600	Memory cache in MB (minimum 3600; increase for better performance)
--cache.database	-	Percentage of cache for database
--cache.gc	-	Percentage of cache for trie pruning
--maxpeers	50	Peer count (more peers = more bandwidth but better connectivity)

Tracing and Debugging

Flag	Default	Description
--tracing	false	Enable Jaeger tracing
--verbosity	3	Log verbosity level
--pprof	false	Enable pprof HTTP server
--pprof.port	6060	pprof port

API Namespaces

Available namespaces for --http.api and --ws.api:

Namespace	Description
eth	Standard Ethereum API (transactions, blocks, state, logs)
net	Network information (version, peer count, listening)
web3	Web3 utilities (client version, SHA3)
personal	Account management (create, unlock, sign)
txpool	Transaction pool inspection (pending, queued)
debug	Debugging and tracing (trace transaction, stack traces)
admin	Node administration (peers, node info, datadir)
arm	Armchain-specific methods
dag	DAG-specific queries (events, epochs)

Subcommands

# Account management
armnode account new           # Create a new account
armnode account list          # List all accounts
armnode account import <key>  # Import a private key
armnode account update <addr> # Update account password

# Validator management
armnode validator new         # Create a new ML-DSA44 validator key
armnode validator convert     # Convert account key to validator key

# Console
armnode console               # Start interactive JavaScript console
armnode attach                # Attach to a running node's IPC
armnode js <file>            # Execute a JavaScript file

# Configuration
armnode dumpconfig            # Dump current configuration
armnode checkconfig           # Validate configuration

# Chain data
armnode import <file>         # Import chain data
armnode export <file>         # Export chain data

# Database
armnode db stats              # Database statistics
armnode db compact            # Compact database

# Snapshot
armnode snapshot prune-state  # Prune state data

# Info
armnode version               # Print version information
armnode license               # Display license

Configuration File (TOML)

Export a configuration file and customize it:

./build/armnode dumpconfig > config.toml

Example TOML structure:

[Node]
DataDir = "/data/armchain"

[Node.P2P]
MaxPeers = 50
ListenAddr = ":5050"
BootstrapNodes = ["enode://[email protected]:5050"]

[Node.HTTPHost]
Addr = "localhost"
Port = 18545
API = "eth,net,web3,arm"
Cors = "*"

[Emitter]
# Validator configuration
ValidatorID = 1

Then start with:

./build/armnode --config config.toml

Environment Variables

Variable	Description
GOPROXY	Go module proxy (used during build)
HOME	Home directory (default datadir location)

Further Reading

• Node Types and Configurations: GC modes, sync modes, database presets, and resource requirements

• Fakenet: Local development network options